PORT PHILLIP BAY


Long-spined Hairy Crab 

Pilumnus acer Rathbun, 1923

View scientific description and taxonomy

Scientific Details

Carapace anterolateral margin with 3 long sharp conical spines with bases not markedly swollen, longest of spines about as long as orbit; carapace with numerous scattered stiff hairs, about 12 hairs forming a fringe behind frontal margin. Cheliped with spines on outer face; walking legs with sharp spines on meri, carpi, but not propodi.

Source: Poore, G.C.B. (2004) Marine decapod Crustacea of southern Australia. A guide to identification (with chapter on Stomatopoda by Shane Ahyong). CSIRO Publishing, Melbourne, 574 pp.

Taxonomy

Phylum:
Arthropoda
Subphylum:
Crustacea
Class:
Malacostraca
Subclass:
Eumalacostraca
Superorder:
Eucarida
Order:
Decapoda
Suborder:
Pleocyemata
Infraorder:
Brachyura
Family:
Pilumnidae
Subfamily:
Pilumninae
Genus:
Pilumnus
Species:
acer

General Description

Carapace anterolateral margin with 3 long sharp conical spines; carapace with numerous scattered stiff hairs, about 12 hairs forming a fringe behind frontal margin. Cheliped with spines on outer face; walking legs with sharp spines on meri, carpi, but not propodi. Up to 22 mm wide.

Biology

Whereas many crabs will attempt to escape when disturbed or captured, pilumnud crabs play dead, curling their legs up to look as inconspicuous as possible. Their camouflage makes them difficult to see even when rocks are turned. Pilumnids are among the most difficult of crabs to identify to species in southern Australia, and close attention to the structure of the first pleopod (gonopod 1) of male specimens will be required to separate some closely related species.

Habitat

Subtidal, to 220 m depth.

Soft substrates

Distribution guide

Southern temperate oceans, including southern Australia.

Species Group

Crabs and allies Crabs

Depth

Shallow (1-30 m)
Deep ( > 30 m)

Water Column

On or near sea floor

Max Size

22 mm

Diet

Organic matter

Harmful

Not harmful but a nip from large claws could be painful

Commercial Species

No

Global Dispersal

Native to Australia

Species Code

MoV 3870

Conservation Status

  • DSE Advisory List : Not listed
  • EPBC Act 1999 : Not listed
  • IUCN Red List : Not listed

Author

article author Taylor, J.

Dr. Jo Taylor is the Sciences Collections Online Coordinator at Museum Victoria.

Author

article author Poore, G.C.B.

Dr. Gary Poore is Principal Curator Emeritus at Museum Victoria.

citation

Cite this page as:
Taylor, J. & Poore, G.C.B., 2011, Long-spined Hairy Crab, Pilumnus acer, in Taxonomic Toolkit for marine life of Port Phillip Bay, Museum Victoria, accessed 17 Aug 2017, http://portphillipmarinelife.net.au:8098/species/5492

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